/*
 * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.
 */
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.sun.org.apache.xalan.internal.lib;

import com.sun.org.apache.xalan.internal.extensions.ExpressionContext;
import com.sun.org.apache.xalan.internal.utils.ObjectFactory;
import com.sun.org.apache.xalan.internal.xslt.EnvironmentCheck;
import com.sun.org.apache.xpath.internal.NodeSet;
import com.sun.org.apache.xpath.internal.objects.XBoolean;
import com.sun.org.apache.xpath.internal.objects.XNumber;
import com.sun.org.apache.xpath.internal.objects.XObject;

import java.util.Hashtable;
import java.util.Map;
import java.util.StringTokenizer;

import jdk.xml.internal.JdkXmlUtils;

import org.w3c.dom.Document;
import org.w3c.dom.DocumentFragment;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.w3c.dom.traversal.NodeIterator;
import org.xml.sax.SAXNotSupportedException;

/**
 * This class contains many of the Xalan-supplied extensions.
 * It is accessed by specifying a namespace URI as follows:
 * <pre>
 *    xmlns:xalan="http://xml.apache.org/xalan"
 * </pre>
 *
 * @xsl.usage general
 */
public class Extensions {
    /**
     * Constructor Extensions
     */
    private Extensions() {
    }  // Make sure class cannot be instantiated

    /**
     * This method is an extension that implements as a Xalan extension
     * the node-set function also found in xt and saxon.
     * If the argument is a Result Tree Fragment, then <code>nodeset</code>
     * returns a node-set consisting of a single root node as described in
     * section 11.1 of the XSLT 1.0 Recommendation.  If the argument is a
     * node-set, <code>nodeset</code> returns a node-set.  If the argument
     * is a string, number, or boolean, then <code>nodeset</code> returns
     * a node-set consisting of a single root node with a single text node
     * child that is the result of calling the XPath string() function on the
     * passed parameter.  If the argument is anything else, then a node-set
     * is returned consisting of a single root node with a single text node
     * child that is the result of calling the java <code>toString()</code>
     * method on the passed argument.
     * Most of the
     * actual work here is done in <code>MethodResolver</code> and
     * <code>XRTreeFrag</code>.
     *
     * @param myProcessor Context passed by the extension processor
     * @param rtf         Argument in the stylesheet to the nodeset extension function
     *                    <p>
     *                    NEEDSDOC ($objectName$) @return
     */
    public static NodeSet nodeset(ExpressionContext myProcessor, Object rtf) {

        String textNodeValue;

        if (rtf instanceof NodeIterator) {
            return new NodeSet((NodeIterator) rtf);
        } else {
            if (rtf instanceof String) {
                textNodeValue = (String) rtf;
            } else if (rtf instanceof Boolean) {
                textNodeValue = new XBoolean(((Boolean) rtf).booleanValue()).str();
            } else if (rtf instanceof Double) {
                textNodeValue = new XNumber(((Double) rtf).doubleValue()).str();
            } else {
                textNodeValue = rtf.toString();
            }

            // This no longer will work right since the DTM.
            // Document myDoc = myProcessor.getContextNode().getOwnerDocument();
            Document myDoc = JdkXmlUtils.getDOMDocument();

            Text textNode = myDoc.createTextNode(textNodeValue);
            DocumentFragment docFrag = myDoc.createDocumentFragment();

            docFrag.appendChild(textNode);

            return new NodeSet(docFrag);
        }
    }

    /**
     * Returns the intersection of two node-sets.
     *
     * @param nl1 NodeList for first node-set
     * @param nl2 NodeList for second node-set
     * @return a NodeList containing the nodes in nl1 that are also in nl2
     * <p>
     * Note: The usage of this extension function in the xalan namespace
     * is deprecated. Please use the same function in the EXSLT sets extension
     * (http://exslt.org/sets).
     */
    public static NodeList intersection(NodeList nl1, NodeList nl2) {
        return ExsltSets.intersection(nl1, nl2);
    }

    /**
     * Returns the difference between two node-sets.
     *
     * @param nl1 NodeList for first node-set
     * @param nl2 NodeList for second node-set
     * @return a NodeList containing the nodes in nl1 that are not in nl2
     * <p>
     * Note: The usage of this extension function in the xalan namespace
     * is deprecated. Please use the same function in the EXSLT sets extension
     * (http://exslt.org/sets).
     */
    public static NodeList difference(NodeList nl1, NodeList nl2) {
        return ExsltSets.difference(nl1, nl2);
    }

    /**
     * Returns node-set containing distinct string values.
     *
     * @param nl NodeList for node-set
     * @return a NodeList with nodes from nl containing distinct string values.
     * In other words, if more than one node in nl contains the same string value,
     * only include the first such node found.
     * <p>
     * Note: The usage of this extension function in the xalan namespace
     * is deprecated. Please use the same function in the EXSLT sets extension
     * (http://exslt.org/sets).
     */
    public static NodeList distinct(NodeList nl) {
        return ExsltSets.distinct(nl);
    }

    /**
     * Returns true if both node-sets contain the same set of nodes.
     *
     * @param nl1 NodeList for first node-set
     * @param nl2 NodeList for second node-set
     * @return true if nl1 and nl2 contain exactly the same set of nodes.
     */
    public static boolean hasSameNodes(NodeList nl1, NodeList nl2) {

        NodeSet ns1 = new NodeSet(nl1);
        NodeSet ns2 = new NodeSet(nl2);

        if (ns1.getLength() != ns2.getLength())
            return false;

        for (int i = 0; i < ns1.getLength(); i++) {
            Node n = ns1.elementAt(i);

            if (!ns2.contains(n))
                return false;
        }

        return true;
    }

    /**
     * Returns the result of evaluating the argument as a string containing
     * an XPath expression.  Used where the XPath expression is not known until
     * run-time.  The expression is evaluated as if the run-time value of the
     * argument appeared in place of the evaluate function call at compile time.
     *
     * @param myContext an <code>ExpressionContext</code> passed in by the
     *                  extension mechanism.  This must be an XPathContext.
     * @param xpathExpr The XPath expression to be evaluated.
     * @return the XObject resulting from evaluating the XPath
     * @throws SAXNotSupportedException Note: The usage of this extension function in the xalan namespace
     *                                  is deprecated. Please use the same function in the EXSLT dynamic extension
     *                                  (http://exslt.org/dynamic).
     */
    public static XObject evaluate(ExpressionContext myContext, String xpathExpr)
            throws SAXNotSupportedException {
        return ExsltDynamic.evaluate(myContext, xpathExpr);
    }

    /**
     * Returns a NodeSet containing one text node for each token in the first argument.
     * Delimiters are specified in the second argument.
     * Tokens are determined by a call to <code>StringTokenizer</code>.
     * If the first argument is an empty string or contains only delimiters, the result
     * will be an empty NodeSet.
     * <p>
     * Contributed to XalanJ1 by <a href="mailto:benoit.cerrina@writeme.com">Benoit Cerrina</a>.
     *
     * @param toTokenize The string to be split into text tokens.
     * @param delims     The delimiters to use.
     * @return a NodeSet as described above.
     */
    public static NodeList tokenize(String toTokenize, String delims) {

        Document doc = JdkXmlUtils.getDOMDocument();

        StringTokenizer lTokenizer = new StringTokenizer(toTokenize, delims);
        NodeSet resultSet = new NodeSet();

        synchronized (doc) {
            while (lTokenizer.hasMoreTokens()) {
                resultSet.addNode(doc.createTextNode(lTokenizer.nextToken()));
            }
        }

        return resultSet;
    }

    /**
     * Returns a NodeSet containing one text node for each token in the first argument.
     * Delimiters are whitespace.  That is, the delimiters that are used are tab (&#x09),
     * linefeed (&#x0A), return (&#x0D), and space (&#x20).
     * Tokens are determined by a call to <code>StringTokenizer</code>.
     * If the first argument is an empty string or contains only delimiters, the result
     * will be an empty NodeSet.
     * <p>
     * Contributed to XalanJ1 by <a href="mailto:benoit.cerrina@writeme.com">Benoit Cerrina</a>.
     *
     * @param toTokenize The string to be split into text tokens.
     * @return a NodeSet as described above.
     */
    public static NodeList tokenize(String toTokenize) {
        return tokenize(toTokenize, " \t\n\r");
    }

}
